This invention relates to solutions suitable as the dialysate in both hemodialysis and peritoneal dialysis of persons suffering from kidney failure.
U.S. Pat. No. 3,993,750, issued to Fox, one of the present inventors, discloses improved resuscitation solutions for the treatment of trauma in humans. The hypertonic solutions of this patent comprise on the basis of 1 liter of solution about 200-300 mEq sodium, about 145-215 mEq chloride, and about 55-85 mEq bicarbonate or acetate or lactate, the sodium to chloride ratio being about 1.4 to 1. Optional ingredients which may be added to the solution include about 1.5-2.5 mEq magnesium, about 3.5-5.5 mEq potassium, up to about 5.5 mEq calcium, about 2.5-3.5 mEq phosphate, and up to about 5% by weight dextrose. These solutions provide the advantages of replacing lost sodium, reducing total water intake and edema, and simulating the sodium to chloride ratio and the electrolyte values of normal blood.
Many of the same considerations involved in formulating a balanced salt solution for treating trauma are also involved in formulating a balanced salt solution for treating kidney failure. In healthy individuals, the sodium content of the body, and hence extracellular volume, is determined by renal excretion of sodium. When the kidneys fail, the patient must be treated by kidney transplant, or else by hemodialysis or peritoneal dialysis.
In hemodialysis, electrolyte and fluid imbalances are corrected by pumping the patient's blood through a device containing a semi-permeable membrane. Water, electrolytes, toxic substances and metabolites in the blood diffuse through the membrane into a solution of salts known as the dialysate. The toxic substances and metabolites are then washed away in the dialysate and the electrolyte values of the blood are restored to normal.
In peritoneal dialysis, a similar dialysate solution is pumped into the peritoneal cavity and surrounds the gut. The same process of diffusion and osmosis of water and toxic substances from the blood takes place through the wall of the gut into the dialysate. Electrolyte values are restored and the toxic substances are washed away in the dialysate.
Because crystalloids diffuse in both directions across the membrane, any electrolyte abnormality in the patient's blood will be corrected by the use of a solution containing normal concentrations of the important electrolytes. Desirably, the dialysate used for hemodialysis and for peritoneal dialysis simulates normal electrolyte values.
Examples of dialysates currently available are the Dianeal solutions sold by Travenol Laboratories, Deerfield, Illinois, which are described in the brochure "Dianeal (Peritoneal Dialysis Solution)" (June 1977).